The influence of corticosterone and corticoliberin on damage of the hippocampus and their relation to cognition

1 ABSTRACT Dissertation deals with the influence of corticoliberin and corticosterone on behavior, memory and learning and the histomorphological changes in the hippocampus. The experiment was performed on rats - long- evans strain, line AV ČR, Krč (male, age ca three months, weight ca 350g). The hormones used were administrated continuously; corticoliberin by the osmotic pump into the right lateral cerebral ventricle for four weeks, corticosterone by the subcutaneous pellet for three weeks. The animals were divided into three experimental groups and one control group. The group [↑CRH] (n=6) osmotic pump-applied corticoliberin (1,5 µg per animal per day), it was made adrenalectomy with substitution by corticosterone subcutaneous pellet (1,4 mg per animal per day). The group [↑CRH↑CS] (n=11) osmotic pump-applied corticoliberin (1,5 µg per animal per day). The third experimental group [↑CS] (n=10) corticosterone was administered by subcutaneous pellet (9,52 mg per animal per day). The control group (n=10) was without any treatment. All groups were subjected to four various behavioral tests - test of active allothetic place avoidance (AAPA), step- through test, conditioned taste aversion (CTA), and test in Morris' water maze (MWM). In the [↑CRH] group was found extension of habituation period caused by anxiety..